In the global solar panel recycling market, the real economic challenge isn’t just recovering glass or aluminum. The highest and most strategic profit margins are hidden in the fine fractions produced during processing—especially the silicon powders and the precious metals they contain.
Professionals in the e-waste disposal sector know that extracting commercial value from these materials requires advanced technological approaches. Recent laboratory analyses conducted by Stokkermill’s R&D department on silicon samples from our facilities revealed a key insight: the percentage of silver (Ag) recovered can be extremely variable.
Here’s why this happens and how to turn that variability into a competitive advantage.
Lab tests confirmed that silver concentrations in silicon powders range from as low as 2,700 up to over 5,000 parts per million (PPM). This wide range stems directly from the history of solar energy technology.
The panels arriving at recycling facilities today were designed at least twenty years ago, before global standards for manufacturing processes existed. On top of that, silver prices were much lower than they are today, which led manufacturers to use it with varying logic and quantities.
This heterogeneity now results in a waste stream that alternates between batches rich in conductive metals (capable of exceeding 5,000 PPM) and panels with much lower yields.
Treating all incoming solar panels indiscriminately—mixing them in a single production stream—is a strategic mistake. Combining high-silver-yield modules with low-yield ones dilutes the concentration of the precious metal in the final silicon powder, inevitably lowering its resale value to refineries.
Stokkermill’s technical and commercial solution relies on strict processing by homogeneous batches. Grouping older panels by production year or construction type before shredding allows for highly predictable outputs. Operators can create silicon batches with specific silver concentrations, isolating high-yield lots to bring a premium product to market.
By adopting our advanced separation technologies combined with smart operational management, we are achieving excellent financial results. Stokkermill’s refining modules precisely concentrate silicon powders, preserving silver and pushing the best batches toward 5,000 PPM.
The global metals market rewards this quality. Today, several batches of enriched silicon processed in our plants are consistently surpassing the commercial threshold of €2,000 per ton.
Profitability in solar panel recycling doesn’t stop at silicon. The industry also targets another strategic fraction: the plastic granulate (mainly EVA), whose value skyrockets when recovered and enriched with the copper fractions from conductive ribbons.
Extracting this compound without losing copper is technologically complex. In this area, we leverage over 30 years of global experience in designing copper wire recycling plants. By transferring this technological know-how to photovoltaic lines, Stokkermill ensures maximum value extraction from both copper and EVA, unlocking an additional, highly profitable revenue stream.
02/03/2026
